Arrangement for fitting a sounding board assembly in a piano



5, 1969 HNzo TAGucHl ARRANGEMENT FOR FITTNG A SOUNDING BOARD ASSEMBLY INA PIANO Filed Dec. 19, 1966 United States p Patent O ABSTRACT F THEDISCLOSURE An arrangement for fitting asounding board in a pianocomprising a rim for supporting the sounding board, lthe rim having acutout into which vis installed a rim plate which is limited to thetreble portion of the piano and which has an upper surface which .isflush with the upper surface of the rim. The rim plate is preferablymade out of special woods Isuch as maple, birch or hickory.

FIG. l is a plan view illustrating an ordinary arrangement for fitting asounding boardassembly into a piano;

FIG. 2 is a-sectional view taken along line II-II of FIG. 1; p v f yFIG. 3 is a 'plan view of an arrangement for fitting a sounding boardassembly into a grand piano in accordance with the present invention; l

FIG. 4 is a sectional view take along line IV--IV 0f FIG. 3;

FIG. 5 is a fragmentary perspective view of the arrangement shown inFIG. 3 with the sounding board assembly dismounted;

FIG. 6 is a plan view of another form of the arrangement according tothe invention as applied to an upright piano; and

FIG. 7 is a sectional view taken along line VII-VII in FIG. 6.

This invention relates to an arrangement for fitting a sounding boardassembly in a piano, and more especially to an arrangement for fitting asounding board assembly to the end of the treble portion of a piano.

An ordinary arrangement for fitting a sounding board assembly in apiano, as shown in FIGS. 1 and 2, consists of a sounding board 1, rib 2,a bridge 3 bonded to the top surface of the sound board 1, and ashoulder rim 4 o which is bonded to the periphery of the sounding board1 at an L-shaped inner rim 4a thereof, and a front rim 5. Such anordinary arrangement has been found disadvantageous because the soundingboard 1 is not fully driven in the treble portion A with the result thatthe piano fails to sound with full volume and full tone in the trebleportion. More particularly, in the adjacent end of the treble portion,the length of the sounding board has different distances from the bridge3 to the hammer-side (corresponding to the under side in FIG. 1 or theleft side in FIG. 2) edge and from the bridge 3 to the antihammer-side(Corresponding to the oblique right side in FIG. 1 or the right side inFIG. 2).

It is an object of the present invention to provide a sounding boardassembly consisting of a sounding board, ribs, and a bridge as abovedescribed, said sounding board assembly being provided at its trebleportion with a rim plate bonded between the top surface of an inner rimand the sounding board in such manner as to facilitate the vibration ofthe sounding board, thereby to increase the volume of the treble portionand improve the tone of the piano during performance.

3,459,091 Patented Aug. 5, 1969 Another object of the invention is toprovide a sounding board assembly provided at the end in the treblep0rtion with a rim plate bonded between the top surface of an inner rimand the sounding board in such manner as to facilitate the vibration ofthe sounding board, thereby to increase the volume of the treble portionand improve the tone of the piano during performance withoutsubstantially changing the sounding area of the sounding board.

According to the present invention, an arrangement for fitting asounding board assembly consisting of a sounding board, ribs, and abridge in piano is characterized in that a rim plate is bonded betweenthe top surface of an inner rim and the sounding board in the treble endportion ofl the assembly, the side edge of said rim plate being disposedin substantially symmetrical position to a hammer-side edge of thesounding board with respect to the fitting line of the bridge of theassembly.

Also, according to the present invention, an arrangement for fitting asounding board assembly consisting of .a sounding board, ribs, and abridge in a grand piano is characterized in that a rim plate is bondedbetween the top surface of an inner rim and the sounding board in thetreble end portion of the assembly, the side edge of said rim platebeing disposed in substantially symmetrical position to a hammer-sideedge or front edge of the sounding board with respect to the fittingline of the bridge to the sounding board.

Further, according to the present invention, an arrangement for fittingva sounding board assembly consisting of a sounding board, ribs, and abridge in an upright piano is characterized in that la rim plate isbonded between the front surface of la rirn and the sounding board atthe back in the treble portion of the assembly, the side edge of the rimplate being disposed in the substantially symmetrical position to ahammer-side edge or upper edge of the sounding board with respect to thefitting line of the bridge of the sounding board assembly.

The present invention will now be described in more detail in connectionwith various embodiments thereof as shown in the accompanying drawings.

Referring to the drawings, `specifically to FIGS. 3, 4 and 5 whichillustrate a sounding board assembly according to the invention asapplied to a grand piano, reference numerals 1 through 5 designate thesame parts as in FIGS. l and 2, 1 being a sounding board, 2 a rib, 3 abridge, 4 a rim, 5 a front rim, and 6 a rim plate which characterizesthe present invention. Below the sounding board 1 of the treble portionA of the sounding board assembly, the side edge 6a of said rim plate 6and the hammer-side edge of the sounding board 1 (corresponding to thepart fixed to the front rim 5 in FIG. 3) are disposed substantiallysymmetrically to each other with respect to the fitting line of thebridge 3. In other words, the rim plate 6 is disposed in the trebleportion A in such relationship as a1=,a1, azT-,az and so forth in FIG.3. In this case, as shown in FIG. 5, the top surface of an inner rim 4ais cut to a depth equal to the thickness of the rim plate 6 at theportion where the rim plate 6 is to be disposed and the rim plate 6 isbonded in position by adhesives such as glue, the rim plate 6 beingflush on the top surface with the top surface of the rest of the innerrim 4a (i.e., the plate has a inlaid relation with the rim). In thefigure, numeral 6b indicates one of the grooves formed on the topsurface of the rim plate 6 like the grooves 4b of the inner rim 4a inwhich ribs 2 previously bonded to the back of the sounding board 1 arepositioned when the sound board assembly is bonded with glue or otheradhesives at its periphery to the top surfaces of the inner rim 4a, therim plate 6 and the front rim 5.

With the construction described above, the present invention isadvantageous because the fitting line of the bridge 3 is in suchposition that the rim plate 6 is provided in the treble portion Awhereby the sounding board 1 can be easily driven for giving adequatesound volume and tone. Further the rim plate 6 is a plate having athickness of to 20 mm., so the portion of the sounding board 1 bondedwith the rim plate 6 may be vibrated, which means that the radiationarea of the sounding board 1 is not lessened. It should be noted thatfrom a View point of driving, the sounding board 1 is supported by therim plate 6 so that the bridge 3 is located substantially in the centerof the driven or free-vibrating portion of the sounding board 1 and thatfrom a view point of sound radiation the area of the sounding boarditself or the radiation area is maintained at original magnitude. Inaddition, the rim plate also vibrates to serve as a sounding radiatingplate.

In FIGS. 6 and 7, there is shown another embodiment of the invention asapplied to an upright piano. In these figures, numeral 1 indicates asound board, 2 ribs, 3 a bridge, 7 a rim, 8 wooden frames, and 6- a rimplate which characterizes the present invention. Below the soundingboard 1 of the treble portion A of the sounding board assembly, the sideedge 6a of the rim plate 6 and the hammer-side edge of the soundingboard 1 (corresponding to the upper part B in FIG. 6) are disposedsubstantially symmetrically to each other with respect to the fittingline of the bridge 3. In other words, the rim plate 6 is disposed in thetreble portion A in such relationship as ali-al1', 1211. a2', and soforth in FIG. 6. In this case, as shown in FIG. 7, the rim plate 6 isworked in such way that the top surface of the rim 7 is cut off and therim plate 6 is bonded thereto to form a top surface substantially flushwith the top surface of the other part of the rim 7 and then thesounding board assembly is bonded thereto.

Most satisfactory results were obtained when rim plates of the inventionmade of maple, birch and hickory, 15 mm. in thickness, were that ingrand pianos.

What is claimed is:

1. A piano comprising a sounding board assembly having a treble portionand including a sounding board having a hammer-side edge, ribs on saidboard, and a bridge across said ribs and generally at an `angle to saidedge, a curved inner rim for supporting said board in said piano, saidinner rim having a top surface, a rim plate curved in correspondencewith said rim and bonded between the top surface of said inner rim andthe sounding board in the treble portion of the assembly, the rim platehaving a side edge disposed in substantially symmetrical position to thehammer-side edge of the sounding board with respect to said bridge, saidrim plate having a top surface provided with spaced grooves to receiveselected of said ribs.

References Cited UNITED STATES PATENTS 1,605,239 11/1926 Johanson 84-1922,538,801 1/1951 Schneider 84-192 RICHARD B. WILKINSON, Primary ExaminerJ. F. GONZALES, Assistant Examiner

